Without a strong start to their careers, Americans in their 20s are less likely to bolster the economy in the short term or to make as much money in the long term.

Reporting from Washington — As the nation struggles with the aftermath of the Great Recession, few groups have suffered greater setbacks or face greater long-term damage than young Americans — damage that could shadow their entire working lives.

Unemployment for 20- to 24-year-olds hit a record high of more than 17% earlier this year. Even for young adults with college degrees, the jobless rate has averaged 9.3% this year, double the figure for older graduates, according to the Labor Department.

Adding to the impact, surveys by the Pew Research Center indicate, a greater share of workers in their 20s lost hours or were cut down to part-time status than any other age group. And their incomes have fallen more sharply, even as they are far more likely than others to say they are working harder than ever.

"These are young workers just trying to establish a connection to work, and it will cause permanent damage to long-term pay. This crisis has the potential for scarring," said Ron Blackwell, chief economist at the AFL-CIO.

The effect of the recession is reflected in the fact that many young Americans who started out living independently are moving back home with their parents because they are unable to survive financially.

Also, new Census Bureau figures show that couples increasingly are postponing marriage and parenthood, waiting for their financial prospects to improve. Meanwhile, more young families are falling into poverty.

"It makes you almost want to cry for the future of our country," said Andrew Sum, director of the Center for Labor Market Studies at Northeastern University in Boston.

These developments, beyond their effects on individuals, are harbingers of significant and painful changes for the whole country.

For decades, adult life, especially for college graduates, began with entry-level jobs that paid well and promised even better things to come. Those bright prospects encouraged young workers to go out on their own, marry and start families — bolstering the overall economy.

But now, with so many unemployed or underemployed — and others underwater on their mortgages or with little hope of buying houses of their own — the spending they once provided simply isn't there now.

Moreover, low starting pay means that future earnings probably will be depressed as well because most workers see their incomes increase slowly and steadily over the course of their careers, not in big jumps.

In the near term, young adults' lower earnings and slower rates of family formation will hurt the still-depressed housing market and crimp consumer spending, which accounts for 70% of the U.S. economy.

In the long run, it could shape the way a whole generation saves and invests, with far-reaching consequences for businesses and the economy.

Young adults, for example, may be less prone to buy stocks because they have been shell-shocked by the recession, said Mark Zandi, chief economist at Moody's Analytics.

He recalled how when he encouraged his own college-age son to put some money in the markets, the advice was met with incredulity. "It dawned on me," Zandi said, "that's his world. In the last 10 years, stock prices have gone nowhere."

Young adults remain very hopeful that things will get better, surveys show, but many face daunting debts that are forcing them to further curtail spending now.

In the two years before the recession, adults younger than 35 were borrowing so heavily — especially for education — that their savings rates ran in the negative teens, according to Moody's analysis of Federal Reserve data.

Since the middle of last year, they have become the most prodigious savers of all age groups, socking away 8% or more of their after-tax incomes.

Until this summer, he and a roommate were living in a sleek two-bedroom apartment in La Verne. Vidales had a full-time marketing job paying $18 an hour and could afford his share of the $2,000 monthly rent.

But then he was laid off, and he's been in and out of temporary jobs ever since. After exhausting his savings, Vidales asked his parents if he could have his old room back in their South El Monte home.

"They told me, 'If you need to come back, then come back. It's not like you're not our son anymore,' " Vidales said. But he took the move back home very hard.

"I felt like I let my parents down," he said. "I'm back to doing my chores [I had] as a kid. It's kind of funny."

Vidales has lots of company.

In the last two years, the Census Bureau said, the number of people ages 25 to 34 living with their parents jumped 8.4% to more than 5.5 million. And a survey by the Pew Research Center suggests that 1 in 8 who are in their 20s "boomeranged" back to a parent's home because of the recession.

With less means, the share of the population 18 and older that is married was just 52% last year — the lowest in more than a century.